EP0523499B1 - Acetohydroxamic acid compound, medicaments containing it and method for the preparation of this compound and the medicaments - Google Patents

Abstract

An acetohydroxamic acid compound of formula I <IMAGE> as such or in form of a complex with beta -cyclodextrin or hydroxypropyl- beta -cyclodextrin specifically inhibits 5-lipoxygenase and is useful in pharmaceutical compositions for prophylaxis and treatment of diseases due to the action of leucotrienes. The acetohydroxamic acid compound may be prepared by reacting 3-thiophenecarboxaldehyde with hydroxylamine or a salt thereof to form the corresponding oxime, reducing the oxime with a boron-containing reducing agent to form N-(thien-3-yl)methyl-hydroxylamine, and introducing an acetyl group.

Description

Polyunsaturated higher fatty acids such as B. the arachidonic acid are used in the metabolism of humans and mammals as substrates for the enzymatically catalyzed formation of physiologically important eicosanoids such. B. prostaglandins and leukotrienes, a substance class also known under the name "Slow reacting Substance of Anaphylaxis" (SRS-A). The prostaglandin formation by the cyclooxygenase (also referred to as "prostaglandin synthetase") and the leukotriene formation by the 5-lipoxygenase is catalyzed.

While the prostaglandins have a number of desired effects in the organism, the leukotrienes or SRS-A are known to be responsible for the development of allergic reactions up to anaphylactic shock, bronchoconstrictions, inflammation, asthma and a large number of other undesirable effects. It has therefore been sought for a long time, over chemically and to be able to have metabolically stable compounds which leave the prostaglandin formation unaffected in the organism, but at the same time selectively or specifically inhibit 5-lipoxygenase and thus prevent the formation of the undesired leukotrienes. For example, acetohydroxamic acid compounds which express 5-lipoxygenase but only little inhibit cyclooxygenase are from a work by Tateson et al. in Brit. J. Pharmacol. (1988) 94 , 528-539. The benzopyran and benzothiopyran derivatives disclosed in EP 412 939 also show a stronger inhibitory effect compared to 5-lipoxygenase.

Acetohydroxamic acid compounds with an optionally substituted phenyl group are described in WO 87/04152 and J. Med. Chem. 31 , 1960-1964 (1988). These compounds have an inhibitory effect on both 5-lipoxygenase and cyclooxygenase.

sowie deren Einschlußverbindungen (Komplexe) mit β-Cyclodextrin oder Hydroxypropyl-β-cyclodextrin sowohl bei parenteraler als auch bei oraler Verabreichung eine weitgehend selektive Hemmwirkung gegenüber der 5-Lipoxygenase besitzen und sich daher zum Einsatz als Therapeutika bzw. Prophylaktika bei Erkrankungen eignen, für die die unter der enzymatischen Wirkung der 5-Lipoxygenase entstehenden Leukotriene als Mediatoren fungieren. Solche Erkrankungen sind beispielsweise Asthma, rheumatoide Arthritis, Psoriasis, allergische Rhinitis, Endotoxin-Schocks, anaphylaktische Schocks, ischämischer Herzinfarkt sowie Störungen der coronaren und/oder cerebralen Gefäße.It has now been found that the new acetohydroxamic acid compound of the formula I

as well as their inclusion compounds (complexes) with β-cyclodextrin or hydroxypropyl-β-cyclodextrin both parenterally and in the case of oral administration have a largely selective inhibitory action against 5-lipoxygenase and are therefore suitable for use as therapeutic agents or prophylactic agents for diseases for which the leukotrienes produced under the enzymatic action of 5-lipoxygenase act as mediators. Such diseases include asthma, rheumatoid arthritis, psoriasis, allergic rhinitis, endotoxin shocks, anaphylactic shocks, ischemic heart attack and disorders of the coronary and / or cerebral vessels.

und deren Einschlußverbindungen mit β-Cyclodextrin oder Hydroxypropyl-β-cyclodextrin.The invention accordingly relates to the acetohydroxamic acid compound of the formula I.

and their inclusion compounds with β-cyclodextrin or hydroxypropyl-β-cyclodextrin.

Another object of the invention is a process for the preparation of the acetohydroxamic acid compound of the formula I and its inclusion compounds with β-cyclodextrin or hydroxypropyl-β-cyclodextrin, which is characterized in that 3-thiophenecarboxaldehyde is reacted with hydroxylamine or one of its salts in the presence of bases to give the oxime , this is reduced by means of boron-containing reducing agents in the presence of acids to N- (thien-3-yl) methyl-hydroxylamine, introduces the acetyl radical into this and the acetohydroxamic acid compound of the formula I thus obtained, if appropriate subsequently by dissolving it in an aqueous solution of β-cyclodextrin or Hydroxypropyl-β-cyclodextrin and freeze-drying this solution converted into the corresponding inclusion compound.

The conversion of 3-thiophenecarboxaldehyde to the corresponding oxime is carried out in a manner known per se, e.g. B. in alcoholic or aqueous-alcoholic solution in the presence of bases, for. B. pyridine, potassium carbonate or sodium acetate at temperatures of 20 - 60 ° C.

The reduction of the oxime is preferably carried out with borohydrides, in particular sodium cyanoborohydride, in acetic acid or ethanolic hydrochloric acid at temperatures between 20 ° C. and 60 ° C. or in alcoholic solution with borane-amine complexes, e.g. B. the borane-trimethylamine complex or the borane-pyridine complex, or with the borane-tetrahydrofuran complex, in each case in the presence of, for. B. 6n hydrochloric acid at temperatures between 0 ° C and 50 ° C (see, inter alia, JB Summers et al., J. Med. Chem. 31 , 1960 (1988)).

erhalten wird, aus der dann durch Zugabe von Basen in Methanol oder Ethanol als Lösungsmittel bei Temperaturen zwischen etwa 20° C und 60° C die O-Acetylgruppe unter Bildung der gewünschten Acetohydroxamsäureverbindung der Formel I abgespalten wird. Als Basen eignen sich z. B. Kalium-, Natrium- und/oder Lithiumhydroxid, Natrium- und/oder Kaliumcarbonat und/oder Natriumhydrogencarbonat, die gegebenenfalls in Form wäßriger 0,1 - 1 normaler Lösungen einer alkoholischen Lösung der Verbindung der Formel II zugesetzt werden.By introducing the acetyl radical, the desired acetohydroxamic acid compound N-hydroxy-N- (thien-3-yl) methyl-acetamide is then obtained from N- (thien-3-yl) methyl-hydroxylamine. For this purpose, N- (thien-3-yl) methyl-hydroxylamine is reacted, if appropriate without prior isolation, with an acetylating agent, preferably acetic anhydride or acetyl chloride, in the presence of acid-binding substances such as pyridine or quinoline, the compound of the formula II

is obtained, from which the O-acetyl group is then split off by adding bases in methanol or ethanol as a solvent at temperatures between about 20 ° C. and 60 ° C. to form the desired acetohydroxamic acid compound of the formula I. Suitable bases are e.g. As potassium, sodium and / or lithium hydroxide, sodium and / or potassium carbonate and / or sodium hydrogen carbonate, which are optionally added in the form of aqueous 0.1-1 normal solutions of an alcoholic solution of the compound of formula II.

To prepare inclusion compounds of the acetohydroxamic acid compound of the formula I with β-cyclodextrin or hydroxypropyl-β-cyclodextrin, aqueous, optionally sodium chloride-containing solutions of the cyclodextrins mentioned are saturated with N-hydroxy-N- (thien-3-yl) methyl acetamide, filtered and lyophilized then the filtrate. The inclusion compounds obtained in this way are notable for very good water solubility with good bioavailability of the active substance present therein.

As already mentioned in the introduction, the acetohydroxamic acid compound of the formula I has a largely selective inhibitory effect on the 5-lipoxygenase, which was determined, inter alia, by in vitro experiments.

To determine 5-lipoxygenase inhibition, aliquots of freshly obtained, heparinized human blood were either mixed with N-hydroxy-N- (thien-3-yl) methyl acetamide in various concentrations or with solvent and incubated at 37 ° C. in a water bath. After 5 minutes, calcium ionophore A 23187 was added in a final concentration of 15 μg / ml blood and incubated at 37 ° C. for a further 30 minutes. The incubation batches were then centrifuged to obtain the cell-free plasma. The content of immunoreactive leukotriene B₄ (“iLTB₄”) in the cell-free plasma was determined by radio-immunoassay “RIA” (³H-LTB₄-RIA, Amersham). The iLTB₄ content of each sample was calculated using a standard curve of LTB₄ standard concentrations prepared with diluted human plasma and calculated as ng iLTB₄ per ml human plasma. Compared to the batches with solvent, the percentage inhibition in the presence of different concentrations of the acetohydroxamic acid compound of the formula I was calculated for the respective concentration. The IC₅₀ value, i.e. H. the concentration which causes 50% inhibition of 5-lipoxygenase was determined for N-hydroxy-N- (thien-3-yl) methyl-acetamide using a linear regression line with 0.3 »molar.

Using cell-free 5-lipoxygenase from basophilic leukemic leukocytes from rats (RBL-1 cells), it was investigated how quickly and to what extent N-hydroxy-N- (thien-3-yl) methyl acetamide from that prepared according to Example 3 Inclusion compound is released. The 5-lipoxygenase activity in the 10,000 xg supernatant of RBL-1 cell homogenates was measured polarographically with oxygen electrodes as measurement parameters. After 5 minutes preincubation of the 10,000 xg supernatant with 75 »M arachidonic acid, 4 mM adenosine triphosphate, 4 mM glutathione and either N-hydroxy-N- (thien-3-yl) methyl acetamide or solvent at 35 ° C, the lipoxygenase reaction was carried out Addition of CaCl₂ started and recorded simultaneously. In the evaluation both the duration of the lag phase and the initial rate of the reaction after the lag phase were included. It was found that the effects brought about by the inclusion compound prepared according to Example 3, both with regard to the prolongation of the lag phase and with respect to the inhibition of the 5-lipoxygenase reaction, are comparable with the effects caused by the acetohydroxamic acid compound of the formula I used in free form. Furthermore, studies with different preincubation times showed that the acetohydroxamic acid compound is released from the inclusion compound without any relevant time delay. The acetohydroxamic acid compound is therefore at least to a large extent freely available even when used in the form of the inclusion compound prepared according to Example 3 in the biological test system.

The influence of the acetohydroxamic acid compound of the formula I on the cyclooxygenase activity was determined with the aid of sheep seed bladder microsomes, suspended in buffer (potassium phosphate 50 mM, pH 7.0), by incubation with either N-hydroxy-N- (thien-3-yl) methyl acetamide or with solvent and radiolabelled arachidonic acid. The IC₅₀ values for the inhibition of cyclooxygenase were determined by means of thin layer chromatography and TLC linear analyzer. It was found that the IC₅₀ values for cyclooxygenase inhibition are significantly higher than the values for 5-lipoxygenase inhibition, i. H. that the acetohydroxamic acid compound of formula I largely selectively inhibits 5-lipoxygenase activity.

These advantageous properties of the new acetohydroxamic acid compound were not foreseeable due to the prior art. For example, published European patent application 0 351 214 describes an acetohydroxamic acid derivative with an inhibitory effect on both lipoxygenase and cyclooxygenase.

European patent application 0 196 184 relates u. a. on acylhydroxamic acid derivatives, for which the inhibitory effect against lipoxygenase and / or cyclooxygenase (in particular also alone against the latter enzyme - compare column 13, lines 26 to 29) is emphasized. It was therefore not possible to predict whether and against which enzyme the new acetohydroxamic acid compound according to the invention could have a largely selective inhibitory effect.

To check the oral in vivo availability as a 5-lipoxygenase inhibitor, the acetohydroxamic acid compound of the formula I was administered orally to male rats (strain Wistar) in a dose of 21.5 mg / kg and the 5-lipoxygenase inhibition resulting after absorption of the compound was ex vivo in Whole blood determined (Tateson et al., Brit. J. Pharmacol. 94 , 528 (1988). Whole blood was drawn from animals after lethal CO₂ anesthesia with the addition of heparin as an anticoagulant. 1 hour after application. Aliquots of the whole blood were taken in a water bath Incubated for 30 minutes with the calcium ionophore A 23187 at a final concentration of 15 »g / ml at 37 ° C. The incubation batches were then centrifuged and the content of immunoreactive LTB₄ (" iLTB₄ ") by radio-immunoassay in aliquots of the cell-free plasma" RIA "(³H-LTB₄-RIA, from Amersham). The iLTB₄ content of each sample was determined using a standard curve of LTB₄-S prepared with diluted rat plasma standard concentrations calculated and calculated as ng iLTB₄ / ml rat plasma. In parallel to the animals treated with N-hydroxy-N (thien-3-yl) methyl acetamide, animals treated orally with vehicle solution were carried in as a control group. The mean value from the iLTB₄ contents of the rat plasmas in this control group served as a 100% value. The respective percentage inhibition of ex vivo LTB₄ synthesis after oral administration of the acetohydroxamic acid compound was calculated as follows: 100 minus 100 times the quotient from the Average of the iLTB₄ contents of the group treated with the acetohydroxamic acid compound and the average of the iLTB₄ contents of the control group (always in ng iLTB₄ / ml). The acetohydroxamic acid compound was inhibited by 95%, which means very good oral availability (5.6 mg / kg was calculated as a dose with half-maximal inhibitory effect after oral administration).

The anti-asthmatic effect of the acetohydroxamic acid compound of the formula I was investigated in anesthetized, curarized and passively ventilated guinea pigs. To trigger an asthmatic reaction, the animals were passively sensitized with anti-ovalbumin serum (0.3 ml intraperitoneally). After 48 hours, the asthmatic reaction was triggered by intravenous administration of 0.2 mg / kg ovalbumin. The immediately occurring bronchoconstriction was measured according to the Konzett-Rössler method (Naunyn Schmiedeberg's Arch. Exp. Path. Pharma. Vol. 195 (1940), pages 71-74) on the basis of the intra-tracheal pressure increase over a period of 15 minutes. Effects triggered by histamine, serotonin and sympathetic countermeasures were demonstrated by intravenous pretreatment of the animals with 2.15 mg / kg mepyramine, 46.4 mg / kg propanolol, 4.64 mg / kg atropine and 1 mg / kg methysergide ( 5 minutes before the bronchoconstriction is triggered by administration of ovalbumin). N-Hydroxy-N- (thien-3-yl) methyl-acetamide was given 60 minutes before oral administration with oval administration, 30 minutes with intravenous administration and 2 minutes before with local administration (intratracheal instillation). The table shows the bronchoconstriction inhibition compared to a control group pretreated only with vehicle solution. Acetohydroxamic acid compound according to example Dose [mg / kg] Application route Inhibition of bronchoconstriction 1 21.5 orally 42% 3rd 21.5 * ⁾ intravenously 49% 3rd 10.0 * ⁾ local 56% *) based on the content of trapped N-hydroxy-N- (thien-3-yl) methyl acetamide

From the results from this table, it is noteworthy that the inclusion compound of Example 3, when administered locally (intratracheal) in approximately half the dose, had a stronger inhibitory effect than with intravenous administration. From the finding that N-hydroxy-N- (thien-3-yl) methyl acetamide was equally effective when administered orally at 21.5 mg / kg as the same compound in the same amount in the form of the inclusion compound from Example 3 in the case of intravenous Administration results in a high absorption rate for N-hydroxy-N- (thien-3-yl) methyl acetamide.

The anti-anaphylactic effect of N-hydroxy-N- (thien-3-yl) methyl-acetamide was also demonstrated in an in vitro model. For this purpose, isolated, spirally prepared tracheal strips of guinea pigs sensitized to ovalbumin (ip application 3 weeks before organ removal, 10 »g together with 20 mg aluminum hydroxide as adjuvant) were sensitized in nutrient solution gassed with carbogen (a mixture of 95% oxygen and 5% carbon dioxide) filled and heated to 37 ° C organ baths and connected with isometric force transducers. After preincubation with mepyramine (histamine switch-off) and indomethacin (inhibition of cyclooxygenase, thereby increasing the anaphylactic reaction), the antigen (ovalbumin) was added to the organ bath in increasing concentrations. The contractions triggered by this were inhibited depending on the concentration by N-hydroxy-N- (thien-3-yl) methyl acetamide, which was added to the organ bath before the anaphylactic contractions were triggered. In the table are the IC₅₀ values, ie the concentrations which bring about a 50% inhibition of the anaphylactic contraction on isolated tracheal strips of the guinea pig, are given. Acetohydroxamic acid compound according to example IC₅₀ [»molar] 1 10.2 3 * ⁾ 18.7 *) based on the content of trapped N-hydroxy-N- (thien-3-yl) methyl acetamide

Due to its largely selective inhibition of 5-lipoxygenase and thus the formation of arachidonic acid metabolites, such as 5-hydroperoxyeicosatetraenoic acid (5-HPETE), 5-hydroxyyeicosatetraenoic acid (5-HETE) and SRS-A, the compound of the formula I according to the invention has numerous physiologically valuable properties , for example anti-anaphylactic, anti-asthmatic, anti-allergic and anti-inflammatory, hypotensive and blood circulation (coronary and cerebral circulation) effects, a reduced leukocyte aggregation and a lower formation of leukocyte thrombi. Since the compound of formula I according to the invention is chemically and metabolically stable and storable for therapeutic use, it is suitable for use as a medicament, e.g. B. as an anti-allergic, anti-anaphylactic, anti-inflammatory, anti-asthmatic, anti-hypertensive, anti-thrombotic agent, as an agent for the prophylaxis or therapy of ischemic heart attack, against disorders of the coronary and / or cerebral vessels or against Crohn's disease.

N-Hydroxy-N- (thien-3-yl) methyl acetamide has only a low toxicity, which is only noticeable at doses far higher than the doses to be used therapeutically or prophylactically. You can therefore in suitable pharma preparations are administered to humans or animals.

Accordingly, the invention also relates to medicaments which contain N-hydroxy-N- (thien-3-yl) methyl acetamide as the active ingredient, optionally in the form of an inclusion compound with β-cyclodextrin or hydroxypropyl-β-cyclodextrin. The amount of active ingredient to be administered to the patient varies depending on e.g. B. the weight of the patient, the route of administration, the indication and the severity of the disease. Taking these factors into account, the active substance content per single dose is generally about 0.01 to 1000 mg, in the case of preparation forms for parenteral administration 0.1 to 1000 mg, in the case of preparation forms for oral or rectal administration 0.1 to 1000 mg and in Formulations for topical or inhalation application 0.01 to 100 mg.

Drugs for parenteral administration can be solutions as well as suspensions, but easily reconstitutable dry preparations can also be used.

Sprays for intranasal or oral application or for the administration of the substances via the bronchi are also suitable forms of application.

Oral preparations of the acetohydroxamic acid compound of the formula I or their inclusion compounds with cyclodextrin or hydroxypropyl-β-cyclodextrin, such as tablets, dragees, capsules, granules, drops and juices or syrups, but also suppositories and percutaneous agents are also expediently suitable for many prophylactic or therapeutic applications Application preparations, such as. B. active ingredients in a depot in dissolved form or, if appropriate, with the addition of plasters containing skin penetration-promoting agents. Become an asset these preparation forms which can be used orally, rectally or percutaneously are produced in such a way that the active substance is released therefrom in a delayed manner so as to ensure that the patient is supplied with the active substance uniformly over a longer period of time (for example 24 hours).

All of the pharmaceutical preparation forms mentioned above are known per se, and since the compound of the formula I according to the invention is chemically stable, incorporation into these preparation forms does not pose any problems for the person skilled in the art. In the preparation of these medicaments according to the invention, it is of course necessary to proceed with the usual care in the selection of auxiliaries, such as carrier materials, solvents, diluents, colorants, flavoring agents, binders, tablet disintegrants, and in particular in the preparation of parenterally applicable preparation forms, sterility and - if they are in are in liquid form - respect isotonicity.

Examples

All temperature information is uncorrected.

The 1 H-NMR spectra were measured at 300 MHz. The chemical shift of the spectroscopic resonance data is given in ppm.

Silica gel 60 (0.040-0.063 mm) from E. Merck, Darmstadt, was used as the stationary phase for the column chromatography.

The thin-layer chromatographic investigations were carried out using "HPTLC finished plates, silica gel 60 F 254" from E. Merck, Darmstadt.

The mixing ratios of the eluents for all chromatographic tests are given in volume / volume.

example 1 Preparation of N-hydroxy-N- (thien-3-yl) methyl acetamide

• a) 3-thiophene carboxaldehyde oxime (syn / anti mixture)
  11.2 g of 3-thiophenecarboxaldehyde, 7 g of hydroxylamine hydrochloride and 5.5 g of sodium carbonate were stirred in 200 ml of ethanol / water (1: 1) for 17 hours at room temperature. The reaction mixture was then poured into 500 ml of saturated sodium chloride solution and extracted three times with 250 ml of ethyl acetate each time. The combined organic phases were washed with saturated sodium chloride solution, dried over magnesium sulfate, filtered and evaporated in vacuo on a rotary evaporator at 40 ° C. 14.19 g of 3-thiophene carboxaldehyde oxime were obtained.
• b) N- (Thien-3-yl) methyl hydroxylamine
  11.45 g of the oxime obtained in Example 1a were placed in 450 ml of glacial acetic acid, then 9 g of sodium cyanoborohydride were added at room temperature and the mixture was stirred at room temperature for 2 hours.
• c) N-acetoxy-N- (thien-3-yl) methyl acetamide
  70.9 ml of acetic anhydride were added to the solution of N- (thien-3-yl) methyl-hydroxylamine obtained according to Example 1b at room temperature. After stirring for 17 hours, the mixture was evaporated in vacuo at 60 ° C., the residue was poured into 700 ml of water after the addition of 150 ml of ethyl acetate, and solid sodium bicarbonate was added to the mixture until the formation of carbon dioxide had failed. The organic phase was separated and the aqueous phase washed with ethyl acetate. The combined organic phases were then dried with magnesium sulfate and evaporated at 40 ° C. in vacuo. After chromatographic purification with hexane / isopropanol / glacial acetic acid (4.5: 0.5: 0.05), 13.27 g of N-acetoxy-N- (thien-3-yl) methyl acetamide were obtained in the form of a yellowish oil.
• d) N-Hydroxy-N- (thien-3-yl) methyl acetamide
  A solution of 3.68 g of the bisacetyl compound obtained according to Example 1c in 56 ml of methanol was mixed with 22.5 ml of 1 molar methanolic lithium hydroxide solution at room temperature and stirred for 45 minutes. The reaction mixture was then added to 150 ml of saturated sodium chloride solution and 40 ml of saturated sodium bicarbonate solution and shaken out with ethyl acetate. The combined organic phases were washed with saturated saline, dried over magnesium sulfate, filtered and evaporated in vacuo at 40 ° C. After chromatographic purification with hexane / ethyl acetate / methanol (4: 6: 0.5) and recrystallization from ethyl acetate, 1.8 g of N-hydroxy-N- (thien-3-yl) methyl acetamide were obtained as a colorless solid with a melting point of Get 92 - 93 ° C.

  1 H-NMR (DMSO-d₆):

  2.03 (s, 3H); 4.66 (s, 2H); 7.03 (m, 1H); 7.31 (d, 2Hz, 1H); 7.43 (m, 1H); 9.87 (s, 1H)

Example 2 Preparation of an inclusion compound with β-cyclodextrin

1.36 g of N-hydroxy-N- (thien-3-yl) methyl-acetamide were added to a solution of 1.8 g of β-cyclodextrin in 100 ml of water at room temperature. After stirring for 17 hours, the mixture was filtered and the filtrate freeze-dried to obtain 3.1 g of a colorless buffer which contained 44% by weight of N-hydroxy-N- (thien-3-yl) methyl acetamide (content determination by comparison of the UV Absorbances of defined solutions of the inclusion compound with those of N-hydroxy-N- (thien-3-yl) methyl-acetamide).

Example 3 Preparation of an inclusion compound with hydroxypropyl-β-cyclodextrin

0.86 g of N-hydroxy-N- (thien-3-yl) methyl acetamide was added to a solution of 5 g of hydroxypropyl-β-cyclodextrin in 10 ml of 0.9% by weight sodium chloride solution and as in Example 2 described further worked. 5.3 g of a colorless powder were obtained which contained 14.3% by weight of N-hydroxy-N- (thien-3-yl) methyl acetamide (content determination in the same way as in Example 2).

The inclusion compounds obtained according to Examples 2 and 3 had very good water solubility, which results in the good bioavailability already shown above. Since the hydroxypropyl-β-cyclodextrin in particular is well tolerated, the inclusion compounds of N-hydroxy-N- (thien-3-yl) methyl-acetamide thus obtained contain products with great application advantages for certain application forms (orally administered, parenterally administered liquid preparations) or powder preparation forms which can be easily dissolved). The following table shows some information on solubility: solvent Solubility in mg / ml of the acetohydroxamic acid compound of Example 1 2nd 3rd Phosphate buffer pH 7.4 / ethanol 4: 1 3rd Phosphate buffer pH 7.4 53 (a) 560 (b) Water / ethanol 4: 1 3rd water 56 (c) 360 (d)

The stated amounts of the inclusion compounds corresponded to the following amounts of N-hydroxy-N- (thien-3-yl) methyl acetamide: a) 22 mg / ml b) 82 mg / ml c) 23 mg / ml d) 53 mg / ml

Claims (10)

1. Acetohydroxamic acid compound of the formula I

   

   and the inclusion compounds thereof with β-cyclodextrin or hydroxypropyl-β-cyclodextrin.
2. Method for preparing the acetohydroxamic acid compound of the formula I

   

   and the inclusion compounds thereof with β-cyclodextrin or hydroxypropyl-β-cyclodextrin, characterised in that 3-thiophenecarboxaldehyde is reacted with hydroxylamine or one of the salts thereof in the presence of bases to form the oxime, the latter is reduced by means of boron-containing reducing agents in the presence of acids to N-(thien-3-yl)methylhydroxylamine, into which the acetyl radical is introduced, and the acetohydroxamic acid compound of the formula I thus obtained is subsequently optionally converted into the corresponding inclusion compound by dissolving in an aqueous solution of β-cyclodextrin or hydroxypropyl-β-cyclodextrin and freeze-drying the said solution.
3. Method according to claim 2, characterised in that N-(thien-3-yl)methylhydroxylamine is converted using an acetylating agent, preferably using acetic anhydride or acetyl chloride in the presence of acid-binding substances, to the compound of the formula II

   

   and the O-acetyl group is subsequently split off by the addition of bases.
4. Method according to claim 2, characterised in that the oxime is reduced to N-(thien-3-yl)methylhydroxylamine using a borohydride, in particular sodium cyanoborohydride in the presence of acids or using a borane-amine complex or the borane-tetrahydrofuran complex in the presence of acids.
5. Pharmaceutical, characterised in that it contains as the active substance the acetohydroxamic acid compound of the formula I as such or in the form of an inclusion compound according to claim 1 and is suitable for parenteral, oral, rectal, topical or intranasal application.
6. Pharmaceutical according to claim 5, characterised in that it contains as the active substance per single dose from 0.01 to 1000 mg of the acetohydroxamic acid compound of the formula I as such or in the form of an inclusion compound according to claim 1.
7. Pharmaceutical according to one or both of claims 5 and 6, characterised in that it is suitable for parenteral application and contains as the active substance per single dose from 0.1 to 1000 mg of the acetohydroxamic acid compound of the formula I as such or in the form of an inclusion compound according to claim 1.
8. Pharmaceutical according to one or both of claims 5 and 6, characterised in that it is in the form of tablets, dragées or capsules, optionally with delayed liberation of the active substance, and contains as the active substance per single dose from 0.1 to 1000 mg of the acetohydroxamic acid compound of the formula I as such or in the form of an inclusion compound according to claim 1.
9. Pharmaceutical according to one or both of claims 5 and 6 in spray form for intranasal or oral application.
10. Method for preparing a pharmaceutical according to one or more of claims 5 to 9, characterised in that the acetohydroxamic acid compound of the formula I, as such or in the form of an inclusion compound according to claim 1, is processed in a known manner with supporting materials, solvents and/or thinners as well as optionally binders, disintegrants and other auxiliary substances and a single dose form of preparation is prepared from the mixture obtained.